Step 1: In any USB cable(for example, the one you use for charging your phone), there are 4 wires.

using usb cable for object counter (1)

Step 2: Use your multimeter to find out which two wires give +5V. One wire should be +5V and the other should be -VE (GND).

using usb cable for object counter (3)

Step 3: Connect the +5V wire to +ve point of screw terminal and -ve to – (minus) point of screw terminal.

using usb cable for object counter (5)

The object counter can now be used. Likewise, you can power up the infrared transmitter also.

using usb cable for object counter (6)

If you are using more than one transmitter and receiver, you can use this type of USB splitter. You can USB splitters with many ports also. 

3 Digit Digital Objects Counter With Laser Module

US $14.95US $19.95

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